FOX Sportscaster Josh Booty was arrested early this morning for DUI -- and was so uncooperative he had to be tased!

Law enforcement sources tell TMZ Booty was taken to the Orange County Jail, where he was booked -- and that's when he went ballistic.

O.C. Sheriff's spokesperson Jim Amormino tell TMZ, "Booty was belligerent and uncooperative." Amormino says his deputies used a taser -- "less than lethal force" -- to contain him.

After being tased, Josh fell to the...